Electric vehicles equipped with an accumulator battery or a fuel cell and driven by a traction motor has been drawn attention because they do not emit carbon dioxide gas during the running. Electric vehicles are provided with an electric motor in a motor room and a driving force generated at the electric motor is transmitted to driving wheels via a transmission, differential gears, and universal joints.
FIG. 6 is a schematic plan view of a conventional electric motor unit consisting of an electric motor, a transmission, and differential gears. As seen in this figure, the electric motor 101 and the differential gears 103, which form the electric motor unit B, are arranged such that a rotating shaft 101a of the electric motor 101 and drive shafts 103a, 104a extending from the differential gears 103 are positioned parallel to each other.
In this figure, reference numerals 102 and 104 designate a transmission and a universal joint, respectively. A referential numeral L′ designates a distance between the shafts 101a and 104a (101a and 103a) when viewing from above. Herein, the reference numeral 103a designates a shaft on the differential gears side and the reference numeral 104a designates a drive shaft on a wheel side.
When considering a collision of a vehicle, it is preferable that the vehicle is provided with a larger crushable zone for absorption of impact. More free space in the motor room is also desired in terms of maintenance. Also, improving the air distribution of the radiator is desired in terms of cooling the motor. Further, it is desired to improve the comfortability with extended vehicle compartment space. Therefore, less install space of the equipment is required in the motor room of the electric vehicle equipped with the electric motor unit B such as illustrated in FIG. 6.
In view of the above, the purpose of the present invention is to provide a motor structure of an electric vehicle, which requires less install space.